EXPLANATION OF THE TLATEK. 11 



PLATE XXXVI. 

 Zygnema Hassallii. 



PLATE XXXVII. 

 Figs. 1 and 2. Zygnema quadratum. — Fig. 3. Zygnema in- 

 termedium. — Fig. 4. Zygnema diductum. — Eig. 5. Zyg- 

 nema vesicatum. — Eig. 6 and 9. Zygnema Jenneri. — Fig. 7. 

 Zygnema dubium. — Fig. 8. Zygnema minimum. 



PLATE XXXVIII, 



Fig. 1. Tyndaridea cruciata. — Figs. 2 and 3. Tyndaridea 

 anomala. — Fig. 4. Tyndaridea lutescens. — Fig. 5. Tyn- 

 daridea bicornis. — Figs. 6 and 7. Tyndaridea insignis. — 

 Fig. 8. Tyndaridea ovalis. — Fig. 10. Tyndaridea stag- 

 nalis. — Fig. 9. Tyndaridea stagnates var. ? 



PLATE XXXIX. 

 Figs. 1 and 2. Tyndaridea censpicua. — Fig. 3. Tyndaridea 

 i miner sa. — Figs. 4 and 5. Tyndaridea, Ralfsii. — Fig. 6. 

 Tyndaridea decussata. 



PLATE XL. 



Fig. 1. Mo ugeotia major. — Fig. 2. Mougeotia gennjiexa. 



PLATE XLI. 



Fig. 1. Zygogonium ericetorum in its terrestrial condition. 

 Fig. 2. Aquatic form of the same. 



PLATE XLII. 



Fig. 1. Mesocarpus scala7'is. — Fig. 2. Mesocarpus scalaris var. 



PLATE XLIII. 



Fig. 1. Mesocarjms intricatus. — Fig. 2. Mesocarpus recurvus. 



PLATE XLIV. 

 Fig. 1. Mesocarpus depressus. — Fig. 2. Mesocarpus ovalis. 



